A novel triazidoruthenium(III) building block for the construction of polynuclear compounds.

Reaction of [Ru(VI)(N)(sap)Cl] with excess NaN(3) affords a novel paramagnetic triazidoruthenium(III) complex [Ru(III)(sap)(N(3))(3)](2-), which is isolated as a PPh(4)(+) salt (1). Reaction of 1 with Ni(2+) and Co(2+) ions produce two isostructural hexanuclear [Ru(4)M(2)] compounds, [Ru(IV)(4)M(II)(2)(μ(3)-OMe)(2)(μ-OMe)(2)(μ-N)(2)(μ-N(3))(2)(μ-O(phenoxy))(2)(sap)(4) (MeOH)(4)] (M = Ni 2 or Co 3). The molecular structures of 1-3 have been determined by X-ray crystallography. 1 is a mononuclear ruthenium(III) compound where three azide ligands are bonded to ruthenium in a meridional fashion, while compounds 2 and 3 are isostructural hexanuclear compounds containing a defective face-sharing dicubane-like core with two missing vertexes. Variable-temperature dc magnetic susceptibility studies have been carried out for 2 and 3. These data indicate that there are four diamagnetic Ru(IV) ions in 2 and 3 and there is ferromagnetic interaction between the two Ni(2+) in 2 and Co(2+) in 3 via the methoxy bridges.